Tailoring Optoelectronic Properties of A–D–A Type Nonfullerene Acceptors with Fused Aromatic Thiophene-Furan Bridges for Efficient Organic Photovoltaics

We report the molecular engineering of new small molecule-based medium band gap nonfullerene acceptors containing a strong electron acceptor backbone of DPP attached to the [Formula: see text]-spacer-based furan linker. We systematically designed five new designed molecules (H1−H5) and studied their structural, optical, photovoltaic and optoelectronic characteristics. We employed advanced quantum chemical approaches to characterize these molecules (H1–H5) and synthetic reference molecule R. The designed molecules exhibit improved light absorption and narrower energy bandgaps in contrast to R. Moreover, a lower excitation energy of these molecules (H1−H5) enables easier excitation and phase separation in the excited states. Analysis of the geometric and physiochemical properties provides evidence of the enhanced photovoltaic and optoelectronic characteristics of these molecules in comparison to the R molecule and other molecules with similar structures that have been previously reported. Among all these designed series, H3 stands out with a minimal 1.99 eV band gap, excellent hole ([Formula: see text] 0.0079 eV) and electron ([Formula: see text] 0.0076 eV) mobility, low binding energy ([Formula: see text] 0.42 eV) and highly red-shifted absorption characteristics. Furthermore, these molecules also displayed good electron and hole mobilities, indicating their tremendous potential in producing high-efficiency organic solar cells. Therefore, this study showcases the molecular modeling and effectiveness of these DPP and furan-containing molecules and their promising potential for organic photovoltaics.